Ever wish you could be a treasure hunter with a secret code-name, tracking down hidden troves? More than two million people worldwide do exactly that by participating in geocaching, a hobby that makes use of a GPS device. Cachers follow coordinates to a cache, where they can sign a logbook using their geocaching name.

Lee McFadden, who helped collect garbage, said that she enjoys geocaching “because I’ve learned some really interesting things about local history and seen some amazing sights I never would have if not for caching.” One of these sights was the old Nike Missile Base on Pinnacle Rock in Plainville on the New England trail. The Nike Missile Base, a relic from the cold war that entered service in 1956, is named for the same Roman goddess of victory as the shoe company.

McFadden recently participated in a geocaching event organized by Randy Wills, also known by his geocaching username “Mr. Echo,” to celebrate Earth Day, April 27. Those who attended found some caches and hauled away over two dozen garbage bags full of trash cleaned up from the trails at the Berlin Blue Hills Conservation Area. “It was everything from wood shingles to about five or seven tires,” Wills said.

Wills said that even though cachers do leave caches in the woods for others to find, many of them “are environmentally conscious, especially about littering.”

Cachers in the Central Connecticut area are “a pretty close-knit community” that regularly holds events, including trips to restaurants, hiking, and even kayaking, according to Wills. Geocaching.com plays a central role in the community by providing a hub where users can find nearby caches, organize events, communicate with other cachers, and even post caches of their own.

Although many cachers are hiking enthusiasts, some caches can be found in urban environments as well. Waterbury resident Joe Medina, who participated in the earth-day clean up, hunted down a cache at a Costco in Waterbury May 4.

Medina said that he enjoys geocaching with his son, and that they sometimes participate with other families as well. One of the best parts about geocaching with kids, according to Medina, is that some of the larger caches, which are generally found on hiking trails, have small toys in them. One of the official rules of geocaching, Medina said, is that if you take an object from a cache, you must leave one of equal or greater value. Kids really enjoy exchanging toys with caches, Medina said.

Caching can get even more complex with “puzzle caches,” which require seekers to solve a riddle to discover the coordinates of the cache. Some hardcore cachers even make do with nothing more than a map and a compass when searching for a cache.

Some caches even move, using a “travel bug” – a metal keychain resembling a dog tag that contains a unique tracking number used to move and verify the bug’s location online.

One of these travel bug caches has even traveled to space. Waterbury native and NASA astronaut Rick Mastracchio, also known as cacher “AstroRM,” has hidden a geocache on the international space station in the form of a travel bug – one he hopes will return to earth and be replaced by a new bug placed by another space-travelling geocacher. Buffalo Wild Wings in Waterbury will be hosting an event for cachers to watch Mastracchio return from the International Space Station on May 13.

Ron Ruel, who also attended the earth day event, has hidden a cache himself in the hiking trails at Wadsworth Park in Middlefield. When hiding a cache “you want to look for a good location, and to put it somewhere that people are going to enjoy themselves,” Ruel said. Caches have to follow certain guidelines, like being far enough away from railroad tracks, private property, and government buildings.

Caches look like “all kinds of things,” Ruel said, but many of them are Tupperware containers, five gallon buckets, or film canisters.

“I’ve seen a fake birdhouse with a cache in it. The possibilities are limitless.”

Sometimes caches are mistaken for trash, although this is very rare, Ruel said. Geocaches have even been mistaken for bombs by police in states across the country. Geocaching.com encourages users not to hide caches near “sensitive infrastructure” to prevent such misunderstandings as the hobby expands. Cachers are also encouraged to use transparent containers and to clearly label all objects as geocaches. PVC pipes, in particular, may look like pipe bombs to law enforcement officials.

Anyone can start geocaching, according to Wills, who said that many people already have the only tool they really need – a GPS device or smartphone. Geocaching.com features videos explaining the rules, and how to get started in playing the real-life treasure hunting game.